CIE Spotlight: Stop jumping the gun – A call for evidence-based invasive predator management

Tim D. and Euan R.
Tim D. and Euan R.

Title: Stop jumping the gun: A call for evidence-based invasive predator management

Authors: Tim S. Doherty and Euan G. Ritchie

Source: Conservation Letters (published online April 2016)

Brief summary of the paper: Invasive mammalian predators are major drivers of species extinctions globally. To protect native prey, lethal control is often used with the aim of reducing or exterminating invasive predator populations. The efficacy of this practice however is often not considered despite multiple practical and ecological factors that can limit success.

feral cat_2 Photo credit Tim Doherty

Here, we summarise contemporary knowledge regarding the use and challenges of lethal control and alternative approaches for reducing invasive predator impacts. As the prevailing management approach, we outline four key issues that can compromise the effectiveness of lethal control: release of herbivore and mesopredator populations; disruption of predator social systems; compensatory predator immigration; and ethical concerns.

We then discuss the relative merits and limitations of four alternative approaches that may enhance conservation practitioner’s ability to effectively manage invasive predators: top-predator conservation or reintroduction; maintaining habitat complexity; exclusion fencing; and behavioural and evolutionary ecology.

Considerable uncertainty remains regarding the effectiveness of management approaches in different environmental contexts. We propose that the deficiencies and uncertainties outlined here can be addressed through a combination of adaptive management, expert elicitation, and cost-benefit analyses. Improved management of invasive predators requires greater consideration and assessment of the full range of management approaches available.